A copy of the database with millions of leaked Facebook data, including telephone numbers, is still online, a security researcher told CNET .

According to the researcher, it is "almost certainly the same data" as the database discovered from Wednesday with data from allegedly over 400 million Facebook users.

The data from the database was probably collected by a third party from Facebook and subsequently put online unprotected, making it freely accessible. People who appear in the database can become victims of identity fraud, among other things.

"Databases of this size are rare, and it is clear from the content that the data from the two databases match," the researcher who discovered the alleged copy of the database told CNET .

The American news site also found the data of Facebook founders Mark Zuckerberg and Chris Hughes in the database. The Zuckerberg telephone number led to an unanswered voicemail, while the person behind the other telephone number claimed to have received the number earlier this year.